Uni-directional transmission with positive engagement and disengagement features

Abstract

Disclosed herein is a uni-directional transmission with positive engagement and automatic disengagement features. The transmission includes a rotatable drive shaft coaxially aligned and housed inside a rotatable hub. Attached to the drive shaft is a uni-directional friction clutch which automatically engages when the drive shaft is rotated in a forward direction. When the friction clutch is engaged, a spline disc located on the drive shaft is forced axially on the drive shaft causing the axially aligned teeth formed on one surface of the spline disc to positively engage the complimentary-shaped, axially aligned teeth formed on the ratchet surface on the hub. When the teeth on the ratchet surfaces are engaged, torque from the drive shaft will be transferred to the hub. A coil spring is disposed on the drive shaft between the spline disc and the hub which acts to automatically disengage the ratchet teeth on the spline disc and the hub when rotation of the drive shaft is stopped or reversed.

I claim: 
     
       1. A uni-directional transmission, comprising: a) a rotatable driven member;   b) a rotatable driving member coaxially aligned with said driven member;   c) a uni-directional clutch disposed on said driving member engaged by said driving member when said driving member is rotated in a forward direction and disengaged from said driving member when rotation of said driving member is either stopped or reversed;   d) a spline disc axially aligned on said driving member, said spline disc being axially moved on said driving member when said driving member engages said uni-directional clutch, said spline disc being engaging said driven member when axially moved on said driving member to interconnect said driving member with said driven member;   e) a coupling means for moving said spline disc axially over said driving member to engage said driven member when said driving member engages said uni-directional clutch, and;   f) a biasing means disposed between driven member and said spline disc for moving said spline disc axially over said driving member to disengage said spline disc from said driven member when rotation of said driving member is stopped or reversed.   
     
     
       2. An apparatus, as recited in claim 1, wherein said uni-directional clutch is a friction clutch. 
     
     
       3. An apparatus, as recited in claim 2, wherein said driving member is a drive shaft. 
     
     
       4. An apparatus, as recited in claim 3, wherein said driven member is a rear bicycle hub. 
     
     
       5. An apparatus, as recited in claim 2, wherein said coupling means is a slidably mounted outer sleeve disposed over said uni-directional clutch, said coupling means further including an axially aligned cam surface formed on said driven member meshing with and driving a plurality of follower teeth formed on said outer sleeve to axially move said outer sleeve against said spline disc to interconnect said spline disc with said driven member.